IF THE COOLING FANS DO NOT WORK:
Well, here's a fast test. The Fan should Should have these colored wires:
Locate the fan sensor (drivers side, near headlight, in rad..) its a 3 wire sensor.
It should have these wires:
Red +12V from fuse 19, 30A under dash
Red/White (low speed trigger)
Red/Yellow (high speed trigger)
Check All fuses under dash. 19, 6 and 4 are key as well as a brass colored bar on the coolant module.
Anyhow. On the fan sensor, unplug it, and jump with a paper clip:
RED to Red/White (fan should come on low speed)
Unplug it. and then;
RED to Red/Yellow. (fan should work on high speed)
IF THE FAN RUNS REPLACE THE SENSOR IN THE RADIATOR.
IF the fan DOES NOT come on jump power TO THE FAN.
IF THE FAN RUNS when jumped directly to power:
If fan does not work replace fan motor.--
If the coolant light on the dash is bad;
Unplug 2 pin connector from coolant bubble.
NOTE:Inspect end of plug for "white crust" or signs of coolant.
If coolant is seen at the end of the plug either on the harness, or the coolant bubble. Replace the bubble.
Coolant light SHOULD NOT BLINK while car is running.
If coolant light blinks;
wires SHORTED in coolant wire harness
Turn car off.
Jump wires on plug (harness side-still unplugged) with a paper clip.
Coolant light should flash within 10 seconds.
If coolant light DOES NOT flash, check;
broken wires in coolant sensor wire harness
cluster plug unseated
Unplug sensor (paper clip).
Light will still flash.
Turn car off.
Insert coolant bubble plug.
Here's a schematic and locations of the components:
This is from a 1996 Jetta. Note Cabrio and VR6 the same as 2.0's - all years. That being said part "1" below (fresh air filter) was never placed into the MKIII production line.